Alert archive / Missouri / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 49, NWS St. Louis, MO

May 8, 2009Washington County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at May 8, 2009, 11:12 AM CDT for Washington County, Missouri. It was in force for 33 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 8, 2009, 11:12 AM CDT (16:12 UTC)
Expired: May 8, 2009, 11:45 AM CDT
In force: 33 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon

County Washington County, MO

The radar

The St Louis radar (KLSX), 96 km from the middle of the area, began a volume at 16:13 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
May 8, 11:40 AM CDT	TSTM WND DMG	5 S Potosi, MO	TREES ACROSS BOTH LANES OF MISSOURI HIGHWAY 21.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 8, 9:21 AM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 4.2 hours before the alert went out and 284 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 3210 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 556 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 141 m²/s²
0-3 km storm-relative helicity: 256 m²/s²
Significant tornado parameter: 2.3
Supercell composite: 9.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS53 KLSX 081612
SVRLSX
MOC221-081645-
/O.NEW.KLSX.SV.W.0049.090508T1612Z-090508T1645Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1112 AM CDT FRI MAY 8 2009

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN WASHINGTON COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 1145 AM CDT

* AT 1110 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DESTRUCTIVE WINDS
  IN EXCESS OF 70 MPH.  THESE STORMS WERE LOCATED ALONG A LINE
  EXTENDING FROM 11 MILES NORTH OF COURTOIS TO COURTOIS...AND MOVING
  EAST AT 45 MPH.

* LOCATIONS IMPACTED INCLUDE...
  POTOSI...MINERAL POINT...IRONDALE...SHIRLEY...LATTY...BELGRADE...
  CALEDONIA AND CADET.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM HAS A HISTORY OF PRODUCING WIDESPREAD WIND DAMAGE. THIS 
IS AN EXTREMELY DANGEROUS SITUATION. SEEK SHELTER NOW INSIDE A 
STURDY STRUCTURE AND STAY AWAY FROM WINDOWS

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

&&

LAT...LON 3775 9110 3799 9110 3799 9064 3786 9064
      3784 9064 3783 9065 3774 9065
TIME...MOT...LOC 1612Z 272DEG 40KT 3791 9099 3773 9099

$$

BRITT

1 follow-up statement

000 
WWUS53 KLSX 081646
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1146 AM CDT FRI MAY 8 2009

MOC221-081656-
/O.EXP.KLSX.SV.W.0049.000000T0000Z-090508T1645Z/
WASHINGTON MO-
1146 AM CDT FRI MAY 8 2009

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN WASHINGTON COUNTY
EXPIRES AT 1145 AM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 4 PM CDT.

LAT...LON 3775 9110 3799 9110 3799 9064 3786 9064
      3784 9064 3783 9065 3774 9065
TIME...MOT...LOC 1612Z 272DEG 40KT 3791 9099 3773 9099

$$

BRITT

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 7, 10:04 PM CDT	Severe Thunderstorm Warning	LSX	Boone, Moniteau	56 min
May 7, 10:26 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Saint Louis	47 min
May 7, 10:52 PM CDT	Severe Thunderstorm Warning	LSX	Boone, Callaway, Cole, Moniteau, Osage	53 min
May 7, 11:20 PM CDT	Severe Thunderstorm Warning	LSX	Callaway, Osage	55 min
May 7, 11:36 PM CDT	Severe Thunderstorm Warning	LSX	Cole, Osage	54 min
May 7, 11:38 PM CDT	Severe Thunderstorm Warning	LSX	Franklin, Gasconade	57 min
May 8, 12:07 AM CDT	Severe Thunderstorm Warning	LSX	Cole, Moniteau	38 min
May 8, 12:15 AM CDT	Severe Thunderstorm Warning	LSX	Crawford, Gasconade, Washington	30 min
May 8, 12:32 AM CDT	Tornado Warning	LSX	Crawford, Washington	28 min
May 8, 12:58 AM CDT	Tornado Warning	LSX	Crawford, Iron, Saint Francois, Washington	37 min
May 8, 1:29 AM CDT	Severe Thunderstorm Warning	LSX	Iron, Madison, Sainte Genevieve, Saint Francois	46 min
May 8, 7:51 AM CDT	Severe Thunderstorm Warning	LSX	Crawford, Franklin, Gasconade, Osage	39 min
May 8, 8:06 AM CDT	Severe Thunderstorm Warning	LSX	Crawford, Franklin	39 min
May 8, 8:38 AM CDT	Severe Thunderstorm Warning	LSX	Franklin, Washington	37 min
May 8, 9:01 AM CDT	Severe Thunderstorm Warning	LSX	Crawford, Iron, Washington	44 min
May 8, 9:12 AM CDT	Flash Flood Warning	LSX	Osage	5 hr
May 8, 9:37 AM CDT	Severe Thunderstorm Warning	LSX	Franklin, Jefferson, Saint Francois, Washington	38 min
May 8, 9:53 AM CDT	Severe Thunderstorm Warning	LSX	Iron, Reynolds	52 min
May 8, 10:01 AM CDT	Flash Flood Warning	LSX	Crawford, Gasconade	6 hr
May 8, 10:02 AM CDT	Severe Thunderstorm Warning	LSX	Jefferson, Sainte Genevieve, Saint Francois	43 min
May 8, 10:32 AM CDT	Severe Thunderstorm Warning	LSX	Madison, Saint Francois, Washington	43 min
May 8, 10:47 AM CDT	Severe Thunderstorm Warning	LSX	Crawford, Iron, Reynolds	58 min
May 8, 11:01 AM CDT	Flash Flood Warning	LSX	Iron, Jefferson, Sainte Genevieve, Saint Francois, Washington	6 hr
May 8, 11:31 AM CDT	Tornado Warning	LSX	Iron, Madison, Saint Francois, Washington	29 min
May 8, 11:45 AM CDT	Tornado Warning	LSX	Sainte Genevieve, Saint Francois	45 min
May 8, 12:05 PM CDT	Severe Thunderstorm Warning	LSX	Madison, Saint Francois	40 min
May 8, 12:18 PM CDT	River Flood Warning	LSX	Osage	20 hr
May 8, 12:18 PM CDT	River Flood Warning	LSX	Cole	28 hr
May 8, 12:27 PM CDT	Severe Thunderstorm Warning	LSX	Sainte Genevieve	50 min
May 8, 12:31 PM CDT	Tornado Warning	LSX	Madison	15 min
May 8, 3:51 PM CDT	Areal Flood Warning	LSX	Crawford, Gasconade	12 hr

Nearby

Severe Thunderstorm Warnings in Missouri, 2009 Every severe thunderstorm warning in 2009

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.